package queue;

class MyCircularQueue {

    private int front;
    private int rear;
    private int[] elem;

    public MyCircularQueue(int k) {
        elem = new int[k+1];

    }
    //1、判断是不是满的？
    //2、把当前需要存放的元素放到rear下标的地方
    public boolean enQueue(int value) {
        if(isFull()){
            return false;
        }
        elem[rear] = value;
        rear = (rear+1)%elem.length;
        return true;
    }
    
    public boolean deQueue() {
        if(isEmpty()){
            return false;
        }
        front = (front+1)%elem.length;
        return true;
    }
    
    public int Front() {
        if(isEmpty()){
            return -1;
        }
        return elem[front];
    }
    
    public int Rear() {
        if(isEmpty()){
            return -1;
        }
        int index = (rear==0) ? (elem.length-1):(rear-1);
        return elem[index];
    }
    
    public boolean isEmpty() {
        return front==rear;
    }
    
    public boolean isFull() {
        if((rear+1)% elem.length == front){
            return true;
        }else{
            return false;
        }
    }
}